I thought we already had enough problems with our food system, what with our corn-based, E. coli-ridden diet. And I thought we already had enough problems with terrorism, what with shoe bombers and underpants bombers running rampant.

So I felt like my head might explode this morning when I read in the Washington Post that terrorists might be targeting our food system for a terror attack. And we're not talking some incompetent, undergarment-fiddling attempt that can be stopped by the guy in seat 13B.

Imagine for a moment a fleck the size of a grain of sand toxic enough to kill an adult  in fact, the most toxic substance on Earth. Now imagine a barrel full of that substance mixed into a shipment of, say, corn, which is then turned into several of the eight zillion processed foods that we so love and shipped to supermarkets all over the country.

The substance is none other than botulinum toxin Type A, the active ingredient in the Botox anti-wrinkle drug. It exists in such tiny amounts in Botox that you'd need hundreds of doses to make a lethal quantity, but now that a global network of counterfeit Botox manufacturers in China and Chechnya have sprung up, getting a terrifying amount of the stuff is no harder than an anonymous Internet order.

The Post reports that "terrorists ... have long been drawn to [botulinum A] as a way to inflict widespread casualties through contamination of food or water supplies." But until now, there was no readily available supply, despite the fact that anyone with solid biological knowledge and $2,000 worth of equipment can make it in a makeshift lab no bigger than a garage.

The U.S. food supply is a natural target for a terrorist poisoning plot, considering that we have centralized it to such an extent that contamination in a single factory regularly sickens people from coast to coast. Inserting even a small amount of botulinum  a Dixie-cup-full, say  into the workings of a processing plant that ships to all corners would have the effect of killing people at random all over the country.

So how likely is this to happen? "We know al-Qaeda has talked about going after food supplies in the United States," the Post quotes an anonymous U. S. Justice Department official. "There are new reasons to be concerned about what they're going to target next."

It's somewhat reassuring that terrorism experts seem to have this threat in their sights. But what are they doing to prevent such an attack?